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International Conference on Communication Systems

作者： Reza Ghazizadeh Pingzhi Fan Institute of Mobile Communications Southwest Jiaotong University Chengdu China

In this paper, a queuing model is introduced to analyze the HCF controlled channel access (HCCA/IEEE802.11e) used in multi-rate wireless local area networks using adaptive modulation and coding, which is a key to wireless networks to increase effective transmission rate. The proposed model which is based on a MAP/PH/1 queue with vacation and time-limited service is useful in optimizing the parameters in cross layer designs and improving spectrum efficiency. Using Markovian arrival process (MAP) for traffic arrival process and phase type (PH) distribution for service process, vacation and non-transmission period make the mode more comprehensive to support practical traffic streams. To formulate the model, powerful matrix-geometric method is employed, and the mutual impacts of some parameters in the MAC and PHY layers are then evaluated and optimized to improve system performance.

关键词： Queueing analysis modulation coding Wireless LAN Traffic control Adaptive systems Programmable control Adaptive control Wireless networks Design optimization Cross layer design

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25 Tb/s Transmission over 5,530 km Using 16QAM at 5.2 bits/s/Hz Spectral Efficiency

25 Tb/s Transmission over 5,530 km Using 16QAM at 5.2 bits/s...

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38th European Conference and Exhibition on Optical Communications (ECOC)

作者： Cai, J. -X. Batshon, H. G. Zhang, H. Davidson, C. R. Sun, Y. Mazurczyk, M. Foursa, D. G. Pilipetskii, A. Mohs, G. Bergano, Neal S. TE SubCom Eatontown NJ 07724 USA

We transmit 250x100G PDM RZ 16QAM channels with 5.2 bits/s/Hz spectral efficiency over 5,530 km using single stage C-band EDFAs equalized to 40 nm. We use coded modulation and all channels are decoded with no errors a... 详细信息

ISBN: (纸本)9781557529503

关键词： 16-QAM modulation coding spectral efficiency Iterative decoding low density parity check codes Tetrapropylene-benzene Sulfonate manufacturing automation protocol MITIGATION ACTION PLANS

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Rate and Power Allocation for 2-Level Superposition Coded modulation Supporting Both Unicast and Multicast Traffic

Rate and Power Allocation for 2-Level Superposition Coded Mo...

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8th International Conference on Wireless Communications, Networking and Mobile Computing (WiCOM)

作者： Fan, YouZhe Tsui, Chi-ying Hong Kong Univ Sci & Technol Dept Elect & Comp Engn Hong Kong Hong Kong Peoples R China

ISBN: (纸本)9781612846835

To support simultaneous multicasting and unicasting service, a 2-level superposition coded modulation (SCM) system with variable code rate allocation is studied. To obtain the most power-efficient scheme for this system, brute-force method can be used to find the best power allocation for each code rate allocation. However, it is very complicated and time-consuming. In this work, the properties of the 2-level SCM capacity is first studied using numerical evaluation and a heuristic method is proposed to efficiently find the optimal rate assignment and power allocation. The simulation results verify the performance of the proposed power allocation method and experimental results show that equal rate allocation scheme provides a power-efficient transmission.

关键词： modulation coding numerical analysis telecommunication traffic

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Comparison of Coded modulations for Trellis-Shaped Single-Carrier PSK with PAPR Reduction

Comparison of Coded Modulations for Trellis-Shaped Single-Ca...

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IEEE Vehicular Technology Conference

作者： Yuuki Nishino Hideki Ochiai Department of Electrical and Computer Engineering Yokohama National University

ISBN: (纸本)9781467318808

Trellis shaping (TS) is known as a flexible technique that controls a transmit symbol sequence such that the resulting transmitted signals meet a certain desired property. Our recent work has shown that TS can generate a near constant envelope signal for PSK signaling even with strict bandwidth limitation through the use of a near rectangular pulse-shaping filter. In this work, we combine this TS approach with several coded modulation schemes and compare their performances in terms of achievable peak power reduction capability and bit error rate over an AWGN channel.

关键词： modulation coding PS-K Phase shift keying AWGN channels bandwidth limitation TBXAS1 gene CACNA1C gene Peak to average power ratio Bit error rate transport stream Pulse shape

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DPCM FOR QUANTIZED BLOCK-BASED COMPRESSED SENSING OF IMAGES

DPCM FOR QUANTIZED BLOCK-BASED COMPRESSED SENSING OF IMAGES

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European Signal Processing Conference

作者： Sungkwang Mun James E. Fowler Department of Electrical and Computer Engineering Geosystems Research Institute Mississippi State University

ISBN: (纸本)9781467310680

Differential pulse-code modulation is coupled with uniform scalar quantization to provide block-based quantized compressed sensing of images. Experimental results demonstrate significant improvement in rate-distortion performance as compared scalar quantization used alone in several block-based compressed-sensing reconstruction algorithms. Additionally, rate-distortion performance superior to that of alternative quantized-compressed-sensing techniques relying on optimized quantization or reconstruction is observed.

关键词： Compressed sensing Quantization DPCM differential pulse code modulation images Rate distortion Reconstruction algorithm COMPRESSED modulation coding Sensing Techniques uniform scalar quantization scalar quantization Compressed sensing

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Successive Interference Cancelation via Rank-Reduced Maximum Likelihood Detection

Successive Interference Cancelation via Rank-Reduced Maximum...

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IEEE Vehicular Technology Conference

作者： Hyukjoon Kwon Jungwon Lee Inyup Kang Mobile Solutions Lab Samsung US R & D Center

ISBN: (纸本)9781467318808

This paper proposes a codeword-based iterative detecting and decoding (K>D) algorithm using a rank-reduced maximum likelihood (ML) detector with pre-whitened interference over multiple-input multiple-output (MIMO) channels. This iterative algorithm operates on the principle of successive interference cancelation (SIC) where all the layers per codeword are decoded together at each iteration. The recent wireless standard requires to encode data bits per codeword, not per layer at multiple antennas. Thus, SIC algorithms based on layer-separating detectors could lose joint information between layers in a single codeword. Instead, the proposed algorithm minimizes this loss by using rank-reduced ML detectors over soft feedback. Simulations are performed on a space-time bit-interleaved coded modulation over Rayleigh fading channels, and demonstrate the proposed SIC algorithm is superior to comparable iterative and non-iterative IDD algorithms.

关键词： maximum likelihood detection codeword Interference cancellation wireless standard Iterative algorithms Raleigh fading channels detector multiple input multiple output systems modulation coding Computer Programming Languages

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Superposition Coded modulation for Cooperative Communications

Superposition Coded Modulation for Cooperative Communication...

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IEEE Vehicular Technology Conference

作者： Hua Sun Soon Xin Ng Lajos Hanzo School of Electronics and Computer Science University of Southampton

ISBN: (纸本)9781467318808

A Turbo Trellis-Coded modulation (TTCM) aided superposition modulation scheme is conceived for a Decode-and-Forward (DAF) based cooperative communication system. More specifically, two source nodes communicate simultaneously with the same destination node via a relay node. Superposition modulation is invoked at the relay node in order to combine and simultaneously transmit the two source signals to the destination node. Hence two timeslots are used to transmit two source signals. Extrinsic Information Transfer (EXIT) charts and power sharing techniques are employed in our design. The performance of the proposed scheme is investigated for transmission over uncorrelated Rayleigh fading channels, which is within about 2 dB of the corresponding capacity.

关键词： TTCM Superposition Rayleigh fading channel EXIT chart Power Sharing Trunk Node cooperative communication Raleigh fading channels modulation coding SUPERPOSITION destination Communication Research TRANSMITTING trellis coded modulation

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Adaptive switching for multiple-input multiple-output multi-mode transmission in broadband wireless networks

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IET COMMUNICATIONS 2011年第13期5卷 1918-1927页

作者： El Kefi, R. Aissa, S. Univ Quebec INRS EMT Montreal PQ H3C 3P8 Canada

In this study, we propose a practical adaptive multiple-input multiple-output (MIMO) transmission approach for broadband wireless multiuser systems. The presented scheme adaptively switches between open-loop and closed-loop MIMO modes depending on the users' channel conditions and required rates as a means to enhance the system throughput and performance. Each mode is a combination of a transmission technique (space-time block coding and/or spatial multiplexing or beamforming) and a modulation/coding scheme. We first evaluate the spectral efficiency of each mode and provide a simple way to select adaptively the best combination of code rate and modulation scheme for open-loop and closed-loop transmission modes in a Rayleigh/composite fading environment. Based on these results, we propose a simple and practical switching criterion that is shown to yield significant spectral efficiency improvements over independent adaptive open-loop or closed-loop schemes for typical multiuser system scenarios. Simulations in an IEEE 802.16e framework are provided and illustrate significant improvements in throughput performance and service fairness.

关键词： Communication switching adaptive MIMO multimode transmission approach telecommunication switching open-loop transmission modes closed-loop MIMO mode user channel condition modulation-coding scheme modulation coding closed-loop transmission modes broadband networks modulation and coding methods broadband wireless networks broadband wireless multiuser system open-loop MIMO mode Rayleigh-composite fading environment IEEE 802.16e framework Radio links and equipment Rayleigh channels adaptive multiple-input multiple-output multimode transmission approach MIMO communication adaptive switching

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Analogue Signalling by Phase Shifting

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IEEE TRANSACTIONS ON COMMUNICATIONS 2011年第9期59卷 2454-2462页

作者： Tosato, Filippo Sandell, Magnus Toshiba Res Europe Telecommun Res Lab Bristol BS1 4ND Avon England

This paper presents a novel method for overlaying an analogue value on top of a digital signal. By adding a phase rotation and a signature sequence to a block of digitally modulated data symbols, this analogue value can be conveyed to a receiver without significant degradation to the underlying digital data. A near-ML estimator is derived which is non-data driven and hence independent of the digital data sequence. It is shown that this method of signalling a value is superior to quantising it and adding it to the digital data stream. We analyse the performance of the analogue and digital methods and also compare them using simulations.

关键词： modulation coding signal processing phase coding phase detection

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Bit-error ratio performance for radio over multimode fibre system using coded orthogonal frequency division multiplexing

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IET OPTOELECTRONICS 2011年第4期5卷 151-157页

作者： Matarneh, A. M. Obayya, S. S. A. Univ Glamorgan Fac Adv Technol Pontypridd CF37 1DL M Glam Wales

In this study, a performance evaluation of radio over multimode fibre system using coded orthogonal frequency division multiplexing (COFDM) is presented. The performance analyses based on bit-error ratio (BER) are extensively investigated. In addition, the effect of fibre length on BER performance is presented. Moreover, the effect of the exponent refractive index profile of the multimode fibre on the BER of COFDM is studied considering maximum likelihood ratio and sub-optimal simplified log likelihood ratio as a soft-bit metrics for soft-decision viterbi decoding.

关键词： soft-decision Viterbi decoding exponent refractive index profile bit-error ratio performance error statistics optical fibre communication Codes modulation coding modulation and coding methods COFDM OFDM modulation Viterbi decoding Microwave photonics Multiplexing and switching in optical communication maximum likelihood ratio radio-over-fibre BER coded orthogonal frequency division multiplexing suboptimal simplified log likelihood ratio radio over multimode fibre system Other topics in statistics

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